I had thought I’d been sleeping unduly long — 9 to 11 hours at times if I can get away with it — until I read a report in the weekly science section of The New York Times on the so-called glymphatic system, which takes out the trash, as it were, from the brain while one is in Never-Never Land.

“So what is removed from our brains as we sleep?” I asked Mary, who is as much of an insomniac as I am a narcoleptic, this morning.

“Is the brain’s janitorial service getting rid of my thoughts?” I called after her. (She was hastily getting ready to drive to work.) “But no, that couldn’t be, for I usually let you do my thinking for me. . . . As for the rest, maybe I’m being brain-washed.”

Indeed. That’s what the article (which, deprived of Mary’s customary sustenance, I did actually read) says, to wit, that the interstitial spaces within the brains of laboratory mice swelled with cerebrospinal fluid that removed toxic proteins (some of which have been associated with Alzheimer’s disease and dementia) while the mice slept or were anaesthetized.

This “glymphatic” system is said to be similar to the lymphatic system, which removes toxins from the rest of the body after physical exercise.

Since one apparently needs uninterrupted periods of the kind of sleep that knits up the raveled sleave of care for the janitorial glial cells to remove the brain’s waste, and thus, presumably, to obviate, or at least forestall, the onset of . . . of . . . yes, yes, Alzheimer’s . . . those who are sleep deprived (as the article says 80 percent of Americans are) would seem to be at risk.

The brain studies — two were cited in The Times article — presage, perhaps, two avenues pharmacological companies may take in the future — one that would “make certain that our brain’s sleeping metabolism is as efficient as it can possibly be,” and one that would “promote the enhanced cleaning power of the sleeping brain in a brain that is fully awake,” a noxious possibility to my somnambulant mind, one that could well cause this idler — who would have, as a result, even more time on his hands! — to lose a lot of sleep.